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When to plant Melon in Jefferson County County,

Jefferson County County gardeners should plant Melon between April 17 and May 8 in spring. With Jefferson County County's Zone 6b climate (last frost April 10), Melon needs 100 days to mature — plant by July 18 for a full harvest.

When to Plant Melon in Jefferson County, MO

Jefferson County, Missouri Zone 6b June

Top priorities for Jefferson County, Missouri gardeners in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 10
Avg. first frost October 26
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
Before July arrives, get these ready
  • First harvests: melon

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Melons are warm-season vine crops that produce sweet, juicy fruits in many varieties including muskmelon and honeydew. They need a long, hot growing season.

Jefferson County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 26, giving you a growing season of approximately 199 days.

At an elevation of 839 feet, Jefferson County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Melon during the growing season.

Jefferson County, MO (Zone 6b) Moderate season
199 days
Last Spring Frost April 10
199 growing days
First Fall Frost October 26
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Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.1

Drainage

Well Drained

Melon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (63 days to spare)
Start indoors: Feb 28 Transplant: Apr 18 🍅 Harvest: Jun 27 – Aug 15
Recommended (50%) ✓ Fits season (66 days to spare)
Start indoors: Mar 6 Transplant: Apr 24 🍅 Harvest: Jul 3 – Aug 21
Safe Start (90%) ✓ Fits season (65 days to spare)
Start indoors: Mar 19 Transplant: May 7 🍅 Harvest: Jul 16 – Sep 3

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Jefferson County

How your county's soil matches Melon's growing requirements.

Soil pH

Your soil pH (5.7–7.1) overlaps with Melon's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Jefferson County is excellent for Melon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Melon.

How to Plant Melon

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Melon

3
successive plantings in your 199-day season

Sow every 8 weeks. Last sowing by Jul 18 to harvest before frost.

Melon Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 515 gal / 100 sq ft

Monthly Watering Guide for Melon

Melon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Melon Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 2.9" 1.4" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 3.2" 1.1" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Melon Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Melon needs ~1,296 GDD — county provides 3,034 GDD Excellent fit

Melon Planting Timeline — Jefferson County, MO

Melon Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 17 Apr 17 – May 8
Harvest July 3 Jul 3 – Aug 21

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June
July Harvest
August Harvest
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

199 days in Jefferson County

Growing Tips for Melon in Jefferson County

Direct sow Melon outdoors after April 10 in Jefferson County when soil has warmed and frost danger has passed.

Common pests for Melon in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 3-4 weeks before transplanting. Plant on raised mounds of compost-enriched soil. Reduce watering as fruits ripen to concentrate sweetness.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Cucumber

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Melon in Jefferson County, MO?

Jefferson County is in Zone 6b with an average last frost of April 10. Plan your Melon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, MO?

Jefferson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 26.

When should I plant Melon in Jefferson County, ?

In Jefferson County, , plant Melon after the last frost (around April 10) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Jefferson County, for Melon?

Jefferson County sits in USDA Zone 6b. Melon grows reliably in zones 4a through 11b, so it's a good fit here.

Can Melon grow in Jefferson County's climate?

Yes — Melon grows well in Jefferson County's temperate climate. Jefferson County averages a 199-day frost-free season, with last frost around April 10 and first frost around October 26.

🌱

Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jefferson County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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